The syntax also supports deleting rows from multiple tables at once. To delete rows from both tables where there are matching id values, name them both after the DELETE keyword: DELETE t1, t2 FROM t1 INNER JOIN t2 ON t1.id = t2.id; … MySQL supports a second multiple-table DELETE syntax.
How delete all data from multiple tables in SQL?
- First, you specify the table name where you want to remove data in the DELETE FROM clause.
- Second, you put a condition in the WHERE clause to specify which rows to remove. If you omit the WHERE clause, the statement will remove all rows in the table.
How can I delete multiple-table records in one query in SQL Server?
13 Answers. You cannot DELETE from multiple tables with a single expression in SQL 2005 – or any other standard SQL for that matter. Access is the exception here. The best method to get this effect is to specify FOREIGN KEYS between the table with an ON DELETE trigger .
Can we delete a record from more than one table simultaneously?
No, a DML statement can affect only one table. Your option is to remove one of the constraints (and potentially enforce it using a trigger instead). I think you need to make it clearer in your question that you have foreign keys pointing in both directions.
How do you delete multiple-table records?
You can specify multiple tables in a DELETE statement to delete rows from one or more tables depending on the particular condition in the WHERE clause. However, you cannot use ORDER BY or LIMIT in a multiple-table DELETE. The table_references clause lists the tables involved in the join.
What is Cascade delete in SQL?
A foreign key with cascade delete means that if a record in the parent table is deleted, then the corresponding records in the child table will automatically be deleted. This is called a cascade delete in SQL Server.
How do I delete multiple table records in one query?
Your eventID in all table will make it work. For deleting records from multiple tables: You could define Foreign Key constraints (which you have defined as EventID) for the other tables that reference the master table’s ID with ON DELETE CASCADE. This would cause the related rows in those tables to be deleted.
How do I delete from multiple tables using inner join in SQL Server?
- begin transaction;
- declare @deletedIds table ( id int );
- delete from t1.
- output deleted.id into @deletedIds.
- from table1 as t1.
- inner join table2 as t2.
- on t2.id = t1.id.
- inner join table3 as t3.
How do you delete a table in SQL?
Using SQL Server Management Studio
- In Object Explorer, select the table you want to delete.
- Right-click the table and choose Delete from the shortcut menu.
- A message box prompts you to confirm the deletion. Click Yes. Deleting a table automatically removes any relationships to it.
How do you delete the contents of a table in SQL?
SQL DELETE Statement
- DELETE FROM table_name WHERE condition;
- Example. DELETE FROM Customers WHERE CustomerName=’Alfreds Futterkiste’;
- DELETE FROM table_name;
- Example. DELETE FROM Customers;
How do I delete a foreign key constraint in SQL Server?
To delete a foreign key constraint
- In Object Explorer, expand the table with the constraint and then expand Keys.
- Right-click the constraint and then click Delete.
- In the Delete Object dialog box, click OK.
What is XYZ in the following SQL statement delete from XYZ WHERE ABC 5?
What is xyz in the following SQL statement? Explanation: The operation being performed in the statement is the ‘DELETE’. The table name is ‘xyz’ and column name is ‘abc’. When this statement is executed, rows having abc value equal to 5 get deleted.
What is Cascade delete in MySQL?
ON DELETE CASCADE constraint is used in MySQL to delete the rows from the child table automatically, when the rows from the parent table are deleted. For example when a student registers in an online learning platform, then all the details of the student are recorded with their unique number/id.
How do I remove all tables?
To delete every row in a table:
- Use the DELETE statement without specifying a WHERE clause. With segmented table spaces, deleting all rows of a table is very fast. …
- Use the TRUNCATE statement. The TRUNCATE statement can provide the following advantages over a DELETE statement: …
- Use the DROP TABLE statement.